There are many different ways to rig a topwater bait for tuna fishing. In general, you want a leader that connects to the main line and some type of swivel that connects the leader to the bait. One of the best ways to rig a topwater for tuna is to add a split o-ring to the leader connecting the leader to the bait. Adding a split o-ring to the swivel increases the overall action of the bait and makes the bait look more natural when you are fishing it.